I think this is an inconsistency in the design of (({Array#values_at})). We can look at a more extreme case:

a[4..100] # => [4, 5]
a.values_at 4..100 # => [4, 5, nil]

And now it doesn't make any sense.

I think the best solution would be to make (({Array#values_at})) be equivalent to successive calls to (({Array#[]})). I have patched (({rb_range_beg_len()})) to handle the extra case and opened a pull request on github.
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